This application is based on the patent application No. 11-204252 filed in Japan, the contents of which are hereby incorporated by reference.
1. Field of the Invention
This invention relates to a camera and particularly to the camera capable of producing a trimmed image to be scheduled for printing a part of photographic image in a subsequent printing process.
2. Prior Art
Generally in a camera using a zoom lens as a photographing lens, the focal length of a finder lens is varied interlocking with the zooming operation to make the angle of view of the photographing lens coincide with the angle of view of the finder.
With such a camera, in normal photographing, the range of a field of view confirmed through the finder is photographed, so it is not a special obstacle to photographing.
Further, it is known that a trimming photographing camera is capable of obtaining a picture having a pseudo telephotographic effect as if it is photographed by a telephoto lens by trimming the top and bottom and left and right of a photographed image in printing. This camera is adapted to trim the top and bottom and left and right of a photographing image plane in a subsequent printing process according to the trimming information preset in photographing and enlarge the image plane to be printed, thereby obtaining a photo having a pseudo telephotographic effect. Such a photographing mode of being scheduled for printing a part of a photographed image plane in printing will be called trimming photographing mode herein after.
Furthermore, it is called a substantial focal length when it includes a real focal length in normal mode, and a pseudo focal length in trimming mode.
In the case of photographing in the trimming mode with this camera, since the angle of view corresponding to the pseudo focal length does not coincide with the angle of view of the finder, it is necessary that only the angle of view of the finder is changed to make the range of visual field of the finder match the image range of a photo obtained by trimming in subsequent printing process, and the range to be trimming photographed can be confirmed through the viewfinder.
Therefore, it has been proposed that in the zoom lens type camera capable of trimming photographing, at the time of trimming photographing, a converter lens is inserted in a finder optical system to change the angle of view of the finder only to the angle of view of pseudo telephotographing (See Japanese Patent Laid-Open No. Hei 4-335332).
In addition to this, it has been proposed that the focal length of an objective lens of the finder optical system is changed to change the angle of view of the finder only (See Japanese Patent Laid-Open No. Hei 5-61093).
In the known zoom lens type camera capable of trimming photographing, zooming operation is conducted in the normal photographing mode, the focal length of the photographing lens is moved to the telephoto side to be set to the maximum focal length, and then when zooming operation is further conducted, it is switched from the normal photographing mode to the trimming photographing mode, and with the zoom lens still set to the maximum focal length, the trimming magnification is increased, whereby the pseudo focal length is increased so as to obtain a printed image with a larger telephotographic effect than that in the normal photographing mode.
In this constitution, it is desired that also in the trimming photographing mode, similarly to the case of photographing in the normal photographing mode, the optimum photographing magnification, that is, the optimum substantial focal length can be set, and it is desirable that in switching from the normal photographing mode to the trimming photographing mode, the substantial focal length is continuously varied to set an arbitrary pseudo focal length. The continuous variation of the pseudo focal length, however, has the disadvantage that since an arbitrary trimming magnification is set in every photographing, setting of trimming magnification in print work becomes complicated.
Therefore, in the camera disclosed in Japanese Patent Laid-Open No. Hei 4-335332, the trimming magnification is previously set to plural, and in switching from the normal photographing mode to the trimming photographing mode, the focal length of a zoom lens is changed to the wide angle side so that the real focal length set in the photographing lens before switching becomes substantially equal to the pseudo focal length in the trimming photographing mode after switching.
According to such constitution, the angle of view of the finder before and after switching the photographing mode is substantially kept constant, but during switching of the photographing mode, the zooming operation is temporarily stopped, resulting in giving a feeling of physical disorder to a user.
Further, in such constitution, it is necessary to provide a space and a special driving mechanism for inserting and separating a converter lens in and from the interior of the finder, which results in the disadvantage that the camera becomes bulky.
On the other hand, in the configuration where the focal length of the objective lens in the finder optical system is changed to change only the angle of view of the finder, there is provided a structure of moving the objective lens of the finder optical system by a finder cam driven interlocking with rotation of the zoom ring of the photographing lens to change the focal length of the objective lens.
The finder cam is provided with two sets of cam grooves, a cam groove used in the case of photographing in the normal mode and a cam groove used in the case of photographing in the trimming photographing mode, whereby in the case of switching from the normal mode to the trimming photographing mode or switching inversely, that is, switching the photographing mode, one of the cam grooves suitable to the photographing mode is selected to move the objective lens of the finder optical system.
However, switching to one of the cam grooves suitable to the photographing mode can not be performed in the middle position of the maximum and minimum focal length of the objective lens of the finder optical system structurally, but switching between the cam grooves can be performed in the position of the maximum or minimum focal length of the objective lens, that is, only at the ends of the cam grooves.
Therefore, the disadvantage is that every time the photographing mode is switched, the zoom ring of the photographing lens is operated to set the focal length of the photographing lens to the maximum or minimum value, that is, to set the photographing lens to the limit position on the telephoto side or the wide angle side, and the finder cam interlocking with the zoom ring should be moved to locate an engagement pin for driving the objective lens of the finder optical system at the end of the cam groove.
The present invention has been made in view of the above circumstances and provides a camera capable of simply switching between two kinds of photographing modes, the normal photographing mode and the trimming photographing mode capable of telephotographing in pseudo by the zooming operation.
Further, the invention provides a camera which is capable of switching between two kinds of photographing modes, the normal photographing mode and the trimming photographing mode and includes a view finder in which a suitable angle of view is always set corresponding to the focal length set in a zoom lens by switching the photographing mode.
Further, the invention provides a camera including a zoom lens in which plural focal lengths are previously set for the normal photographing area corresponding to the normal photographing mode and the trimming photographing area corresponding to the trimming photographing mode, respectively, and a view finder in which a suitable angle of view is always set corresponding to the focal length set in the zoom lens.
Another aspect of the invention will be known from the detailed description of the invention with reference to the attached drawings.